Improvement in lifting-jacks



A. DOM.

Improvement in'Lift ing-Jacks, N0. 132,753. Patented Nov. 5,1872.

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ALEXANDER DOM, OF MOUNT HEALTHY, OHIO.

EMPROVEMENT IN LlF'l'lNG-JACKS.

Specification forming part of Letters Patent No. 132,753, dated November 5, 1872.

.To all whom it may concern:

Be it known that 1, ALEXANDER DOM, of Mount Healthy, Hamilton county, Ohio, have invented a certain new and useful Improvement in Lifting-Jacks for Carriages, &o., of which the following is a specification:

Nature and Objects of Invention.

My invention consists of the combination of lifting-rod and link or clutch, pitman and lever, and a friction-catch, so arranged as to retain by a simple adjustment the lifting-rod in an elevated position.

Description of Drawing.

Figure 1 is a transverse vertical section of a jack embodying my improvements, showing the lifting-rod in an ascending position. Fig. 2 is a similar section, showing the rod locked to a lifted position, while the pitman and clutch are seen dsecending for another lift. Fig. 3 shows in a similar section the position of the parts at the moment when the lever is leveled to a horizontal position by the guide and allows the rod to fall freely. Fig. 4. is a side elevation of a jack embodying my invention, showing the handle, pitman, link, and a portion of the rod.

General Description.

A is a smooth rod of iron or other suitable metal, having a head, a, at right angles to its axis at its upper extremity, and sliding freely up and down in the guides E E, in which it is loosely fitted. It is loosely embraced by one end of a clutch or link, 13, as shown in the drawing, whose other end, B, is linked into the lower extremity of a bent pitman, 0, whose superior extremity is attached to the curved pump-handle lever D, which is pivoted at d, on a pin attached to the frame. This lever being operated like the handle of a common pump; the clutch B slides down the rod until the contact of the guide E brings it to a horizontal position; the succeeding stroke of the lever brings it to the position shown in Fig. 2, in which the inner superior edge and the outer inferior edge gripe the rod so firmly as to raise it with the link until the stroke is completed, when the curved shape of the lever and pitman, shown in Fig. 4, bringing the supportingpoint of the rod into a continuous line with the two pivots of the lever and pitman, the rod remains locked in its raised position. Should it be necessary to raise the rod still higher, the friction-catch F, Fig. 2, operating on the same principle as the link B, may be so adj usted as to retain the rod in its elevated position, while another stroke is made with the lever, thereby doubling the elevation of the rod.

Claim.

The combination of rod A, friction-link B, pitman O, lever D, guide E, and angular reversible friction-catch F, arranged and acting substantially in the manner and for the purpose specified.

In testimony of which invention I hereunto set my hand.

ALEXANDER DOM. Witnesses:

FRANK MILLWARD, I. L. WARTMANN. 

